As one who has owned and used Leicas occasionally over 40 years of shooting, with lenses from 15mm to 135mm, and with and without power winders, the following are my comments on why I enjoy shooting Leicas so much. Almost all my Leica shooting was black-and-white; I can't comment on color aspects.

1. Bulk. The Leica body is about half the bulk of a Nikon F when you actually pack it in your kit, and a little lighter. The lenses are about half the bulk of the same focal length and f/ number (though the fast tele lenses approach the size of the fast Nikkors). A full Leica kit with motorized M4 or M6, 21mm, 35mm, 90mm, can fit in the same space as a Nikon with one fast lens.

2. Distortion. Now that we have Photoshop this is less important, but in the old days, the rangefinder wideangles had significantly less distortion than the reflex wideangles. There was no easy way to correct this distortion. There's a big change from the 21mm Super-Angulon to the later lenses in distortion. (My 21mm Nikkor had low distortion too, but no advantage of reflex viewing.) This began to change when Leica put light meters inside the camera - the meter system required more separation between lens and film plane, and Leica started using retrofocus designs even in its rangefinder wideangles wider than 35mm. When the 35mm Summicron was redesigned, the new lens had more distortion than the older designs. Even a subtle amount of distortion can change the appearance to the eye - I think the mental impression of sharpness even changes when the 90-degree angles become slightly wider. I think the attempt to increase sharpness across the entire field also resulted in designs with more distortion.

3. Image quality. The Leica fast lenses were exceptionally sharp and contrasty compared to reflex lenses. Comparing my 35mm Summilux (the little one from the 60s and 70s) to the 35mm f/1.4 Nikkor - the Leica images at f/1.4 were sharp and contrasty while the Nikkor images seemed hazy by comparison. Stopping down, the lenses both improved, but the Leica always seemed crisper.

4. Focusing wide lenses. The depth of field of wide lenses, even fast ones, makes them hard to focus on the ground glass of reflex cameras, particularly in dim lighting. The rangefinder of the Leicas by contrast is easy to focus in dim light, and for wideangles is much more precise than needed to achieve sharp focus. No contest.

5. Quiet. Until the F100, which substantially quieted the Nikon shutter and mirror operation, the Nikons were much louder than the Leicas. You can barely hear the soft "schluck" of a Lieca shutter more than a few feet away unless it is very quiet. The snap and crash of a Nikon shutter and mirror is much louder and sharper. The F100 is still much louder than a Leica, but substantially quieter than the F, F2 and F3.

6. Viewfinder frame wider than the lens field. Having the bright frame and seeing outside it is great for action shots and anticipating what's going on outside the frame.

7. Uninterrupted view. You always see the image in a Leica, and you see the image the instant of the shot. With reflex cameras, it's the precise instant of the shot that you CAN'T see. What did I get? That's an issue.

8. Camera vibration at slow shutter speeds. The Leica was easier to get good available-light shots with at 1/15 or 1/8 second because of the smaller amount of camera mechanical vibration. At 1/4 and slower, I think they're probably equivalent, because your ability to keep the camera fixed overshadows any camera-caused vibration.

Disadvantages:

1. Parallax. The 2-inch separation between the finder and the lens axis is important in shooting architecture and interiors, and shooting close to the subject. It's generally not critical for reportage. In only a very few instances was this a problem for me in using Leicas.

2. Shooting rate. Even with the power winder, Leicas don't provide the high frame rate of the Nikon.

3. System range of capability. With reflex viewing, the system becomes much more capable, expanding to photomicrography, macrophotography, long telephotos, etc. No comparison.

4. View of depth-of-field effects. The reflex allows you to view directly the effects of depth of field, if you use this capability. The view is different than the print, but with practice the print view can be anticipated. With a rangefinder, you're seeing everything sharply, so you have to anticipate depth of field effects from experience.

5. Autofocus. Not available on Leica or other classic rangefinder cameras. There is nothing to prevent a modern rangefinder camera from having autofocus, but you start losing the advantages of compact size and light weight.

In your very good essay you forgot to mention filters, for example it is almost impossible to use grads or polarizer on a rangefinder because you can not see the effect, not an issue if you do not use filters at all.
Today Nikon could build some hybrid design using sensor and live-view to overcome most of drawbacks rangefinders have, but it will also require that Nikon design new mount to be able to use advantages rangefinders have.

ted2001 said:
For my use an electronic viewfinder or a camera with LCD only is not a rangefinder. It must have an optical viewfinder - that great window Leica owners love so much.

I totally agree with you, Ted. I NEED a viewfinder. I can't STAND that some brands (hem . . . hem . . . Panasonic Lumix) who've built a small, compact "DSLR" without a viewfinder. A few months ago, I walked into Samy's Camera and one of the salesmen there was bragging about the new "amazing" Lumix and he was trying to pitch it to me as the next greatest thing. I was terrified when I saw there wasn't a real viewfinder: it was just a digital image like what you see in Live View or something. I really don't want to see all cameras coming to that.

All I saw in that poor, pathetic Lumix was a point-and-shoot with interchangeable lenses. A cross-breed.

TJGilbert21 said:
All I saw in that poor, pathetic Lumix was a point-and-shoot with interchangeable lenses. A cross-breed.

Yeah that's kinda the whole point. Small package with the ability to change lenses. I've seen quite a few Nikon "People" using the Ep1/2 and GH/F1s with Nikkor adapters on them. When I say "people" I mean important people who, knowing that even they have such cameras, leave me to believe that Nikon is working on one too.

First thing that comes to my mind as well is the fact that they are so damn small. They are easy to hide/conceal making them ideal for usage in dangerous spots, security orientated spots or a place which has problems with theft. There have been so many world famous shots taken with rangefinders over the decades which adds to their mystique as well.

I had an M8 before, but was not pleased with the images as I hated putting a UV filter on that beautiful 28mm ASPH 2.8 Leica lens. The M9 makes me salivate though..

mb makes a great point about another disadvantage of rangefinders - the use of filters such as graduated ND and polarizers, where the effect is almost impossible to judge without seeing through the imaging lens. Leica did make (perhaps still makes?) a polarizer with a separate viewing window to see the effect, but it was too expensive for me at the time.

I use a polarizer a lot for landscapes for darkening hazy skies and increasing the saturation of green leaves and grass, so the Leicas didn't get used much for landscapes. I never had JUST rangefinders, I always had the Nikons as my primary cameras. The Leicas were for traveling light, and for unobtrusive street shooting and available-light shooting indoors.

mb, Patmann, I agree about filter use being a limiting factor. I also would never only use rangefinders, they're just the perfect compliment to SLR's.

As I've thought about this thread, I've also thought about how much I'd miss the wide zoom range my 16-85 provides for street shooting. The D90 with 16-85 isn't that big and is rather inconspicuous, particularly if you don't draw attention by staring at the LCD after each shot (I keep mine turned off - it also saves battery power.) At about $1,400 I could get mugged 5 times before it would cost the same as an M9. A moment of uncertainty?

Right after commenting about composing with the LCD on your other thread, ted, I have to mention again that a digital rangefinder doesn't suffer from the filter problem you're discussing. They have a built-in separate viewfinder to check filter effect—the LCD. That said, I still can't see how it's worth 5-7 D90 kits. Call me uninformed.

I use a variety of rangefinders, primarily the Russian Leica copies, and a Yashica Electro35 GS, which needs an overhaul cause I wore it out over the summer. They're super compact, have quicker focusing action in low light due to the split image method of focus, and are generally quieter than SLRs, especially if they are equipped with leaf shutters. Lenses are smaller, and in terms of screw mount optics, are far less expensive than SLR optics.

I can fit my Zorki 1C with a collapsible 50 in my sweatshirt pocket or jacket no problem. It's only slightly longer than a compact, and the image quality is up to par with my larger 35mm SLRs, and will yield 15-25mp scans without much effort.

it's tiny, plus I can shoot with both eyes open, effectively super imposing the rangefinder spot into my normal vision. This means I have a more than 100% viewfinder at all times, and I can see what's going on all around me. Already mentioned, but there's no finder black out either, so you know exactly what you captured on film.

The "filter" problem is only an issue for me when I'm mostly shooting landscapes. Rangefinders for me are optimized for street and documentary shooting. The vision issue Chris mentions is the key factor for me. (money not-with-standing)

jonnyapple said:
Right after commenting about composing with the LCD on your other thread, ted, I have to mention again that a digital rangefinder doesn't suffer from the filter problem you're discussing. They have a built-in separate viewfinder to check filter effect—the LCD. That said, I still can't see how it's worth 5-7 D90 kits. Call me uninformed.

It isn't worth really, not unless you must have that red badge ...
Badges?... We don't need no... stinkin' badges! Red or otherwise now do we?